# Intermittent transport of bacterial chromosomal loci

## TL;DR

This paper introduces a minimal theoretical model combining fractional Brownian motion with intermittent forces to explain the short-time dynamics of bacterial chromosomal loci, capturing both subdiffusive and active relocations.

## Contribution

It presents a novel minimal model for bacterial chromosomal loci dynamics, integrating intermittent forces with fractional Brownian motion, validated against high-resolution tracking data.

## Key findings

- Identifies characteristic time scales of intermittency in loci movement.
- Shows active relocations are associated with increased local noise.
- Provides a framework to understand rapid bacterial chromosomal locus relocations.

## Abstract

The short-time dynamics of bacterial chromosomal loci is a mixture of subdiffusive and active motion, in the form of rapid relocations with near-ballistic dynamics. While previous work has shown that such rapid motions are ubiquitous, we still have little grasp on their physical nature, and no positive model is available that describes them. Here, we propose a minimal theoretical model for loci movements as a fractional Brownian motion subject to a constant but intermittent driving force, and compare simulations and analytical calculations to data from high-resolution dynamic tracking in E. coli. This analysis yields the characteristic time scales for intermittency. Finally, we discuss the possible shortcomings of this model, and show that an increase in the effective local noise felt by the chromosome associates to the active relocations.